1. Time-resolved three-dimensional magnetic resonance velocity mapping of aortic flow in healthy volunteers and patients after valve-sparing aortic root replacement 
Michael Markl, PhD, Mary T. Draney, PhD, D. Craig Miller, MD, Jonathan M. Levin, MD, Eric E. Williamson, MD, Norbert J. Pelc, ScD, David H. Liang, MD, PhD, Robert J. Herfkens, MD 
The Journal of Thoracic and Cardiovascular Surgery 
Volume 130, Issue 2, Pages (August 2005)
DOI: /j.jtcvs
Copyright © 2005 The American Association for Thoracic Surgery Terms and Conditions

2. Figure 1
Schematic illustration of data acquisition, data processing, and blood-flow visualization for 3D MR velocity mapping. Top: Electrocardiogram gating and respiratory control (left) and 3-directional velocity encoding (right) for the 3D velocity mapping. After R-wave detection, a real-time estimate of the phase in the respiration cycle was generated and used to adjust the phase-encoding amplitude such that the data matrices mimicked the acquisition in a single respiratory cycle. During each RR interval, a fraction of 4 time-resolved 3D volumes needed for 3-directional velocity encoding was collected, and this process was repeated over consecutive cardiac cycles until all data matrices were completely filled. The 3 spatial components (vx, vy, and vz) of the velocity data were derived by generating phase difference images from the reference (Ref.) and respective velocity-sensitive data set. Bottom left: After retrospective data interpolation, Fourier transform, noise filtering, and eddy current correction, 4 time-resolved 3D data sets were generated reflecting thoracic anatomy (Mag), as well as 3 spatially registered blood-flow velocity components (vx, vy, and vz). The image shown here depicts a single sagittal oblique slice during systole in the acquired 3D volume and 20 reconstructed cardiac phases. Each velocity image represents quantitative Cartesian velocity components in which the grayscale values correspond to the velocity magnitude and direction. Bottom right: blood-flow visualization with 3D streamlines in the thoracic aorta. The individual lines represent traces along the instantaneous velocity vector field in a systolic time frame and are color-coded according to velocity magnitude in meters per second. ECG, Electrocardiogram.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /j.jtcvs )
Copyright © 2005 The American Association for Thoracic Surgery Terms and Conditions

3. Figure 2
Three-directional velocity vector fields in two 2D planes transecting the ascending aortic flow trace for a healthy volunteer (top) and patients who underwent T. David-I (bottom left) and T. David-V (bottom right) valve-sparing aortic root replacement. The planes were positioned normal to the opened aortic valve (top left) to depict color-coded blood flow velocities near the left coronary (LC) and right coronary (RC) cusps. Formation of blood-flow vortices is clearly visible in all cases (arrows). Note that the systolic aortic valve anatomy and corresponding 2D plane positions are shown only for the volunteer. Movies corresponding to this figure are available online.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /j.jtcvs )
Copyright © 2005 The American Association for Thoracic Surgery Terms and Conditions

4. Figure 3
Comparison of average scores for systolic vortex formation as a result of visual image inspection by 3 independent observers. The individual bars represent results for the left, right, and noncoronary cusps. In all cases, comparable systolic vorticity was found for both coronary cusps, whereas noncoronary vortex formation was significantly enhanced for patients who underwent root replacement that included creating graft neosinuses (TD-V, T. David-V technique; TD-V-S, T. David-V-Smod technique). The error bars indicate ±1 standard deviation.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /j.jtcvs )
Copyright © 2005 The American Association for Thoracic Surgery Terms and Conditions

5. Figure 4
3D streamlines reflecting systolic blood flow in the thoracic aorta for a patient after T. David-V valve-sparing aortic root replacement. The images on the top right and in the bottom row depict magnified regions including the ascending aorta and the aortic arch, as well as a 2D plane including the aortic valve. Pronounced right-handed helical flow in the ascending aorta (AAo) and arch during mid and late systole is evident (DAo, Descending aorta). A movie corresponding to this figure is available online.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /j.jtcvs )
Copyright © 2005 The American Association for Thoracic Surgery Terms and Conditions

6. Figure 5
Late systolic 3D particle traces reflecting aortic flow for a patient after T. David-I valve-sparing aortic root replacement. The image on the right shows a magnified region that includes the ascending aorta. Retrograde flow (white arrows) along the inner wall of the distal ascending aorta (AAo) is clearly visible (DAo, Descending aorta). A movie corresponding to this figure is available online.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /j.jtcvs )
Copyright © 2005 The American Association for Thoracic Surgery Terms and Conditions